Verify idempotency #5
Description
After refactoring from one static method to full-blown system using Startup.cs and Dependency Injection (#2), it is not so easy anymore to see if the functionality is still idempotent.
an idempotent operation is one that has no additional effect if it is called more than once with the same input parameters.
Go through the solution and make sure calling PostComment is idempotent.
See if it is possible to add a neat test to keep it idempotent.